Alexander Puck Neuwirth
Theoretical and computational particle physicist working on precision predictions for high-energy collisions: perturbative QCD and electroweak corrections, photon production, and Monte Carlo event generators.
I am a research fellow in the Dipartimento di Fisica "Giuseppe Occhialini" at the University of Milano-Bicocca. I completed my PhD at the University of Münster, where I worked on combining fixed-order QCD calculations with parton showers for real and virtual photon production. Alongside this research, I develop open-source scientific software (pylhe, LHEUTILS) and contribute to shared particle-physics infrastructure, including LHAPDF, HepMC, Rivet/YODA and Gentoo Linux.
Research
All research areas →-
Photon Fragmentation Functions
Effective parton-to-photon fragmentation functions extracted from PYTHIA, distributed as LHAPDF grids.
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Low-Mass Dileptons
Virtual-photon conversion to lepton pairs: Kroll-Wada vs. parton-shower descriptions.
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Photon+Jet Production
NLO QCD photon-plus-jets predictions matched to parton showers via POWHEG and MiNLO.
Selected publications
All publications →-
Photon Fragmentation Functions in LHAPDF: Existing Sets and a Pythia-Based Extraction
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Conversion of Photons to Dileptons in the Kroll-Wada and Parton Shower Approaches
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Prompt Photon Production with Two Jets in POWHEG
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pylhe: A Lightweight Python Interface to Les Houches Event Files
Selected talks
All talks →-
MC4EIC 2026
“Photon Fragmentation Functions extracted from Pythia stored in LHAPDF”
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PyHEP 2025
“PyLHE in 2025: New features and improvements”
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LMee Workshop 2025
“From Kroll-Wada to Parton Showers: Modern Approaches to Photon-to-Dilepton Conversion for ALICE”
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Forward Physics and QCD at the LHC and EIC 2023
“Prompt photon production with up to three jets in POWHEG”
Software
All software →-
babyyoda
Python package providing YODA histogram objects through the Unified Histogram Interface (UHI), for working with HEP analysis data (as produced by Rivet) in a more Pythonic way.
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feynamp
Converts Feynman diagrams written in feynml into scattering amplitudes, for further processing with tools such as FORM or SymPy.
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feynml
An XML dialect and Python toolkit for representing Feynman diagrams in a renderer-independent way, separating physical/topological content from its graphical representation — similar in spirit to HTML/CSS.
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guess_factor
Small C++ tool (with Python bindings) that guesses an unknown multiplicative factor between two numbers, by searching combinations of configurable bases (e.g. 2, π, 3, physics constants) raised to small integer exponents.
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HEPi
Python interface for gluing together several HEP generator and analysis tools (e.g. from HEPForge) into unified, reproducible workflows.
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LHEUTILS
Command-line utilities for filtering, converting and processing Les Houches Event (LHE) files and Monte Carlo event samples.
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pyfeyn2
Python package for drawing Feynman diagrams across many render engines (matplotlib, PyX, TikZ, ASCII, Unicode, feynmp, DOT). A fork of the original pyfeyn, extended with new rendering backends and manual or automatic vertex placement.
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pylhe
Lightweight, pure-Python library for reading and writing Les Houches Event (LHE) files, the standard Monte Carlo event format in high-energy physics. Part of the Scikit-HEP ecosystem.
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smpl
Simplified plotting and fitting in Python.
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STRAP
Statistics TRAcking Protocol — a small, Unix-style text protocol for accumulating per-event statistics during scientific simulations, with a Rust-based GUI for visualizing the resulting data.